Tyrell Williams’ speed made him one of Chargers quarerback Philip Rivers’ best deep threats. Williams averaged 16.3 yards per reception during his first four seasons. (Photo by Scott Varley, Daily Breeze/SCNG)

Tyrell Williams, who started 37 games for the Chargers the past three seasons, is moving on to join the Oakland Raiders, according to ESPN.

Tyrell Williams signed with the Chargers as an undrafted free agent following the 2015 draft, and flourished as a reliable down-the-field target for quarterback Philip Rivers. But his departure was an expected move. The Chargers already had an in-house replacement with Mike Williams, and had other positional needs to address.

Tyrell Williams was arguably the best wide receiver available on the open market. The Raiders reportedly agreed to give Williams a four-year, $44 million deal with a max value of $47 million and $22 million guaranteed. That’s a big financial jump from the base salary of $2.9 million he made with the Chargers in 2018.

“(Williams) got progressively better and better and better,” Chargers general manager Tom Telesco said in January. “He kind of took it to the next level this year, and he certainly earned his second contract.”

After only playing in four games as a rookie out of Western Oregon, Williams started in 12 games in 2016. He formed one of the better receiving duos in the NFL with Keenan Allen the past three years.

Williams’ career numbers don’t stand out because the Chargers had many options with Allen, Mike Williams, and tight ends Hunter Henry and Antonio Gates. But speed is highly coveted, and Tyrell Williams displayed that by averaging 16.3 yards per reception during his first four seasons.

Williams will now be teaming with former Pittsburgh Steelers star wide receiver Antonio Brown for the Raiders, who continue to stay active during free agency.

Gilbert Manzano grew up reading the Pasadena Star-News, and now he’s the Chargers beat writer for the Southern California News Group. Manzano moved back to Pasadena after working three years for the Las Vegas Review-Journal as a Raiders and boxing reporter. The Cal State Northridge graduate spent two seasons as a breaking news editor for NFL.com. The Spanish-speaking lefty likes to go on runs with his dog, Cam.